Data

Photograph of dust acoustic waves, from a Q-machine experiment in a lab of Professor D'Angelo and Professor Merlino. The white bands are concentrations of dust particles, which become charged when they are introduced into a plasma. An acoustic wave propagating in the horizontal direction causes compression and rarefaction of this suspension of charged dust particles.	Photograph of charged microspheres suspended in a plasma, from Professor Goree's group. The microspheres acquire a large charge, and repel one another, so that they arrange themselves in a regular pattern, like atoms in a crystalline lattice. In the inset the "bonds" between nearest neighbors are drawn as red lines.	Bispectral plot of ion waves in a plasma in Professor Skiff's lab. This kind of plot is a scheme for detecting the presence of nonlinear interactions between waves at different frequencies, when seeking an understanding of turbulence.
A snapshot of an Alfvén wave in Professor Kletzing's experiment using the Large Plasma Device. The colors correspond to the wave's magnetic field strength, which is modulated in a pattern determined by the experimenter's choice of the phases of sinusoidal voltages applied to each element of the wave launcher.	Magnetic reconnection simulation, from a collaboration of Professor Scudder and Dr. William Daughton of Los Alamos National Laboratory. In many plasmas, such as the solar wind downstream from the Earth, magnetic field lines cross in an X-point, which appears at the center of this image. At this X-point, plasma flows in from above and below, and out the sides. Magnetic field lines rearrange themselves in a process called reconnection. The electrons in the regions shown in yellow here find a way to ignore the magnetic field, instead of spiraling around B as they usually do.

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